The sliding tribological behaviour of Cr-(WC-Co) coating against wood (beech) as counterpart was investigated using a duplex treatment of low carbon steel(DIN 18CrMo4). The duplex treatment consists of LPC (low pressure carburising) + R.F magnetron co-sputtering of Cr and WC-Co. Pin-on-disk configurations in dry condition wear tests were performed. The wear scars of the coatings were evaluated using optical profilometry, scanning electron microscopy (SEM/EDS) and the wear mechanisms were consequently discussed. The aim of this work is to study wear mechanisms on the wood pin/disc couple. It was concluded that best behaviour was observed in the case of higher Cr content coating

BELIARDOUH, Nasser Eddine

KALELI, Hakan

NOUVEAU, Corinne

English

SAM;  the Arts et Métiers ParisTech open access repository

Science Arts & Métiers (SAM)
is an open access repository that collects the work of Arts et Métiers ParisTech
researchers and makes it freely available over the web where possible.
This is an author-deposited version published in: https://sam.ensam.eu
Handle ID: .http://hdl.handle.net/10985/9990
To cite this version :
Nasser Eddine BELIARDOUH, Corinne NOUVEAU, Hakan KALELI - Wear performance of duplex
treated low alloyed steel against wood (beech) as static partner - Journal of the Balkan
Tribological Association - Vol. 20, n°1, p.84-92 - 2014
Any correspondence concerning this service should be sent to the repository
Administrator : archiveouverte@ensam.eu
* For correspondence.
WEAR PERFORMANCE OF DUPLEX TREATED LOW ALLOYED 
STEEL AGAINST WOOD (BEECH)AS STATIC PARTNER
N. E. BELIARDOUHa*, C. NOUVEAUb, H. KALELIc 
a Laboratoire ingénierie des surfaces (LIS), Université BADJI Mokhtar, BP12; 
23 000 Annaba, Algeria
E-mail: beliardouh_23@yahoo.fr
b Laboratoire Bourguignon des Matériaux et Procédés (LaBoMaP), Arts et
Métiers ParisTech de Cluny, Rue Porte de Paris, F-71250 Cluny, France 
c Yildiz Teknik Universitesi, Makine Fakultesi, Makine Muhendisligi Bölümü, 
Otomotiv Anabilim Dali, 34349 Besiktas, Yildiz, Istanbul, Turkey 
ABSTRACT
The sliding tribological behaviour of Cr-(WC-Co) coating against wood (beech)
as counterpart was investigated using a duplex treatment of low carbon steel(DIN 
18CrMo4). The duplex treatment consists of LPC (low pressure carburising) + 
R.F magnetron co-sputtering of Cr and WC-Co. Pin on disk configurations in dry 
condition wear tests were performed. The wear scars of the coatings were evalu-
ated using optical profilometry, scanning electron microscopy (SEM/EDS) and 
the wear mechanisms were consequently discussed. The aim of this work is to 
study wear mechanisms on the wood pin/disc couple. It was concluded that best 
behaviour was observed in the case of higher Cr content coating. 
Keywords: duplex treatment, Cr-(WC-Co) coating, wood, wear.
AIMS AND BACKGROUND
Woodworking tools should be hard and need to have low friction coefficient. 
However, wood cutting tools should not be too hard, because surface of wood 
must be smooth. In the last decade, some works1,2 were conducted to replace HSS 
(high speed steel), carbides (WC-Co) and other ceramics by coatings like CrN 
or TiN. Chromium nitride family, used for wood cutting tools, shows a superior 
performance than family of titanium nitride coatings. Tribological tests were car-
ried out for several specimens prepared from different types of woods, i.e. oak, 
beech, spruce and pine3–5. Abrasive wear properties of a large variety of conifer-
ous wood and hardwood are reported in Ref. 6. Beech wood (Fagussylvatica) has 
good strength properties, a high abrasion resistance and a density d = 0.73 g/cm3. 
It can be cut, planed, drilled and milled easily. Beech is the most abundant broad-
leaf tree species in central Europe and the quality of beech round wood is suitable 
for high quality rotary cut veneer5 in manufacture of furniture, floor, various car-
pentry of the interior. The aims of this study are: (i) to optimise the carburising 
of the steel substrate and deposition conditions of Cr-(WC-Co) coatings; (ii) to 
investigate the wear resistance of duplex treated samples against wood (beech) in 
view to their application on wood cutting tools.
EXPERIMENTAL
Sample elaboration. The substrate used in this work was a commercial low al-
loy steel DIN 18CrMo4. Before thermo-chemical treatment, the samples were 
polished with P800 paper, ultrasonically cleaned, and finally introduced into a 
vacuum furnace ‘BMI Furnace’. The carburising gas was ethylene (C2H4) and the 
temperature was 900°C. The total durations of the boost/diffusion stages were 
120 min (carburising C1) and 105 min (carburising C2). After the carburising pro-
cess, samples are in-situ quenched in a high pressure N2 environment (500  kPa), 
subsequently annealed at 200°C for 120 min, and finally cooled in a 100 kPa N2 
atmosphere. The Vickers hardness values of C1-treated surface layer is Hv.100= 
768 ±5 and the C2-treated samples yield Hv.100 = 654 ± 5. Additionally, carbon 
analysis of the surface layer yields 0.667 wt.% and 0.615 wt.% for C1 and C2 treat-
ments, respectively. Both of treated C1 and C2 samples present the same hard-
ness’s value at the core of the substrate (Hv.100  ~ 300) and approximately the same 
depth of carburised layers (550–
600 µm). A standard and typical 
microstructure was developed af-
ter carburising process. At the top 
layers, the microstructure consists 
of martensite phase and cementite 
(Fe3C) with evidently a few quan-
tities of γ retained austenite. After 
that, Cr(WC-Co) coatings onto 
carburised surface samples were 
elaborated as can be seen in Fig. 1.
Deposition of Cr-(WC-Co) 
coatings was done by RF mag-
netron sputtering in a modified 
commercial system (Nordiko 
Coating Cr-(WC-Co)
Substrate
Fig. 1. SEM micrograph: cross-section view of du-
plex treated samples. The Cr-(WC-Co) layers devel-
oped a dense structure
3500). Substrate to target distance was 8  cm and the base pressure was 6×10–5 
Pa. The targets were Cr (Neyco, 99.95%) and WC-6 wt.% Co(Ampere, 99.5%). 
The substrates were initially chemically cleaned, followed by a 12 kV DC glow 
discharge pulsed plasma (25 ms on/50 ms off) for 5 min at an argon pressure of 
2 Pa. The chemical composition and mechanical properties of coatings are pre-
sented in Table 1. As can be seen, 2 different compositions were obtained by F101 
(Cr:W = 1.53:1) and F102 (Cr:W = 1.21:1), respectively.
Samples characterisations. Wear properties of the coatings were evaluated un-
der dry sliding condition at room temperature using a pin-on-disk tribometer 
(CSM  HT1000) and Tribox 4.1.1 software. The two main standards referring 
to the pin-on-disk tribometer are DIN 50324 and 
ASTM G 99 – 95a (Ref. 7). The pin-on-disc tests 
were performed with the test configuration sche-
matically illustrated in Fig. 2. The pin wood with a 
diameter of 6 mm is positioned at 45° on the holder 
and loaded against a rotating disc. Only cemented 
(C1 and C2) and cemented +coated (F101 and F102) 
samples were studied. 
In order to approach real contact conditions, e. 
g. the wood process as peeling of beech, test param-
eters were chosen appropriately as listed in Table 2. 
A particular preparation is needed when tests are 
conducted with wood counterpart: the pin was cut 
perpendicular to fibres (length 20 mm; ∅ of 6 mm) 
from a specific specimen of beech tree provided by 
a regional sawmill. It was then polished to remove 
any chips and immersed into hot water (70–75°C) 
for 24 h. 
After the tribo-tests, the profiles of the wear tracks 
were measured by 3D optical profilometry(VEECO, 
Wyko NT-1100) and the wear rate was calculated us-
ing conventional equations. The wear tracks, wear 
debris and edges of wood pin were analysed by 
Table 1. Chemical composition and mechanical properties of coatings
Coatings
code
Chemical composition
(at. %) O2 ~ 0.7
Thickness
(µm)
Hardness
(GPa)
The Young modulus
(GPa)
C Cr Co W
F101 22.3 41.6 8.3 27.1 2.3 26.4 324.1
F102 23.3 35.4 8.8 31.8 2.2 26.7 331.3
Table 2. Parameters of experi-
mental wear tests
Parameters 
Humidity 
Sliding speed 
Normal load
Track radius
Sliding distance
Temperature
40%
2 cm/s
5 N
4 mm
200 m
20°C
45°
2 
1
3 
1 – pin holter
2 – pin wood
3 – disk
Fig. 2. Pin-on-disk tests
SEM/EDS, using a Jeol JSM-5900LV microscope. 
RESULTS AND DISCUSSION
Coefficient of friction evolution. As can be seen in Fig. 3a, when sliding against 
the wood pin, the coefficient of friction (COF) of the C1 specimen at the start in-
creases rapidly after that it decreases slightly. Then it reached a maximum value 
of 0.65 (500 cycles), followed by a sudden decrease to 0.25 (6000 cycles). This 
phenomenon is also observed when the applied load equals to 1  N. At the end of 
test, the friction coefficient increases to its maximum value of ~0.8–0.85. How-
ever, the coefficient of friction of the C2 sample rises slowly and gets stabilised at 
the end of test about 1–1.2 (Fig. 3b). Both curves show a run-in period followed 
by a friction coefficient increase. The C1 sample presents a lower COF (0.85) than 
the C2 sample (1.15) after 8000 cycles of sliding against wood pin.
When duplex treated samples were tested, the coefficient of friction showed 
a run-in period, and afterwards an increase in slope of curves, as can be seen in 
Fig. 3. The F102 coating had a high run-in friction and showed a short period of 
stabilised COF of around 0.6–0.65 for (C1+F102) and (C2+F102). On the contrary, 
the F101 coating shows a nearly constant evolution of COF. For both (C1+F101) 
and (C2+F101) samples, after a run-in period, a value about 0.2 was reached.
Wear analysis. After a tribotest, SEM analysis of the uncoated samples surface 
revealed a large wear track (1.5–1.8 mm), and substantial amount of wear particles 
on its edges. These remarks are valuables for all samples treated C1 and C2. An 
example of wear track of disk seen on C1 samples is shown in Fig. 4a: inside the 
circular wear track, wear debris were formed. SEM micrographs show also finest 
and parallel grooves as result of ploughing by oxide particles (third body wear). 
0.8
0.6
0.4
0.2co
ef
fic
ie
nt
 o
f f
ric
tio
n
co
ef
fic
ie
nt
 o
f f
ric
tio
n
0 2000 4000 6000 8000
cycles 0 2000 4000 6000 8000cycles
1.2
1.0
0.8
0.6
0.4
0.2
carburising C1+F102 coating
carburising C2+F102 coating
carburising C2+F101 coating
carburising C1
carburising C2
carburising C1+F101 coating
a b
Fig. 3. Friction behaviour of the duplex treated samples(C1.2 +F101 and C1.2+F102) compared with 
uncoated samples (C1; C2) in interaction with pin wood as counterpart
Moreover, the wear scar of the counter face, i.e. the edge of the pin wood became 
smooth as reported in Fig. 4b. Some particles (oxides) are incrusted inside the 
fibber of wood and a few ‘chips’ are formed at its circumference. Thus initially, 
at the asperity contact tips, formation of oxides film and, after reaching a critical 
thickness, breaking of this oxide film (cracks in Fig. 4a) occur as debris forma-
tion. Consequently the first step of wear mechanism for the cemented samples 
sliding against a wood pin is an oxidative wear and the second step is a mild 
abrasive wear mechanism.
All of the duplex treated samples sliding against pin wood showed the largest 
wear scar but not very deep (Fig. 5a,b). The coatings are then efficient and well 
protected by the cemented steel. Few of particles inside circular wear trackwere 
observed for both coatings F101 and F102 (Fig. 5b). Based on SEM micrographs, 
no difference was evident between F101 and F102 coating wear tracks was shown 
and can explain the coefficient of friction evolution in Fig. 3. EDS analysis of the 
cracks  
1.76 mm 
200 µm
grooves
particles
100 µm  
inserted particles 
from wear debris
S.D 
S.D 
edge of pin = worn  surface
a
b
Fig. 4. Example of SEM micro-
graphs of: wear track on disk 
carburized C1 (a) and the cor-
responding counterpart worn 
surface of pin wood after pin-on-
disk test (b). The insert image was 
obtained by CATIAV5 software
worn surface and the debris inside wear scar (Fig 5 a,b) reveals only the presence 
of elements of coating (Cr, W, Co): no iron (Fe) signal or oxygen (O) were found, 
consequently the wear track is free of oxides. In comparison to the carburised 
samples and according to the above mentioned results, it can be concluded that the 
wear mechanism undergone by discs was only a slight abrasion wear.
Figure 6 shows the wear scar on wood pin after 200 m sliding distance against 
duplex treated samples. Considerable difference exists between surface morphol-
ogy of pin edge after sliding against F101 (Fig. 6a) and F102 (Fig. 6b) coatings. 
The wear scar of the pin in the case of the F101 coating shows few quantities of 
particles, dispersed on a smooth wood surface. These particles contain metallic 
and organic elements of wood as revealed by EDS analysis spectra. Again, no 
iron peak (Fe) or oxygen (O) were detected; that proves that coating in not en-
tirely destroyed yet. Therefore, the detachment of the coating was presented in 
the form of wear debris. Some scratches (furrows) parallel to sliding direction are 
also present and are caused by particles (no oxides) between the contact surfaces. 
The small amount and size of the observed particles are not sufficient to cause an 
abrasive wear mechanism. Besides, the COF evolution curve of the F101 coating 
(Fig. 3), regardless the substrate, indicated that was a mild wear compared to the 
Fig. 5. Duplex treated samples: example of SEM micrographs of wear tracks and corresponding 
EDS spectra at point ‘x’: C1+F101 (a) and C1+F102 (b)
W W 
WCr  Cr  
Cr  Co
W b
X 
W 
800 µm
1  2   3    4    5  6    7   8   9  10   11 
kev
kev
S.D  
S.D  
1  2    3   4  5   6  7   8    9    10    11
a
X 
800 µm
C Co
O 
Co  W
W 
Cr  
Cr  Co
W 
W 
F102 one. As a consequence, no evidence of abrasive wear was found. We sup-
pose that movement of particles during sliding can be due to rotation or rolling 
as reported in literature8–10. The coatings are worn gradually, slowly and with 
continuous wear with micro-chipping of small coating fragments in connection 
to surface defects. The SEM micrographs of the pin worn surface sliding against 
F102 is shown in Fig. 6b. This part of the wear scar shows a significant amount 
of adhered counter material which indicates a stronger adhesion between contact 
surfaces. This is in agreement with the corresponding friction curve in Fig. 4, 
which shows significantly higher and more fluctuating values as compared with 
the friction curve displayed by F101 coating. The wear mechanism in this case is 
adhesive.
Quantitative analysis. From the wear track profile obtained by 3D profilometry, the 
volume loss and wear rate of disc were calculated, for all the samples. The wear scar 
of the counterpart (pin wood), is an ellipse. Then major and minor semi-axes were 
measured by profilometry and to calculate the volume loss CATIAV5 software was 
used (see the inserted image in Fig. 4b). The results are presented in Fig. 7.
Fig. 6. Example of SEM micrographs of worn surfaces of wood pins against C1+F101 (a) and 
against (C1+F102) (b). EDS analysis spectra carried out the particles indicate by X
300 µm
S.D
X 
a
particles
S.D
300 µm
furrows
WW Co  Cr 
Cr  
W 
W 
Na  
O 
Cr  
C 
1  2  3  4   5    6   7   8   9  10  11 
WW CoCr  
Cr  Ca  K Cl
W 
W
Na  
Cr  
C 
1  2  3  4   5    6   7   8   9  10  11
X 
b
kev
kev
The highest wear rate was ob-
tained for wood pin and the lowest for 
the duplex treated samples. An inter-
mediate wear rate is observed for the 
cemented samples. This is probably 
due to the softer hardness of the wood 
pin in comparison to the cemented 
and duplex treated steel samples. Be-
sides, the cemented samples showed a 
similar wear rate value as the duplex 
C1/F101 and C2/F101 or C1/F102 and 
C2/F102 treated samples. Neverthe-
less, the duplex treated samples (wear 
rates K of about 1 to 2×10–6 mm3/N  m) 
were much more wear resistant than 
the only cemented ones (wear rates K of about 7×10–6 mm3/N m).
It can also be seen that the F101 coating has a lower wear rate than the F102 
one probably due to its low COF (0.2). This confirms SEM analysis and the COF 
evolution curves.
CONCLUSIONS
According to the above-mentioned results the following conclusion can be made:
– An oxidative followed by an abrasive wear mechanism is observed when
cemented samples were in contact with a wood pin.
– After sliding against the duplex treated samples, the severity of sliding
friction depends strictly on the adhesive interactions of the wear debris. In the 
case of the F101 (Cr:W = 1.53:1) coating, a few and small metallic particles were 
detached and trapped between the contact surfaces, acting as a protective layer 
and thus reducing the friction coefficient while an adhesive wear characterised 
by larger and metallic debris was observed for the F102 (Cr:W = 1.12:1) coating;
– If the application of the steel is wood machining, the C1/F101 or C2/F101
duplex treatments are recommended to protect the steel cutting tools against wear 
and to have the lowest COF;
– The effect of a duplex treatment is obvious here to improve the wear re-
sistance of the steel in comparison to carburising and in view to apply it in wood 
machining.
ACKNOWLEDGEMENT 
The authors would like to thank Dr. M. J. Walock, Dr. A. Zairi, Pr. P. Jacquet, and 
D. Lagadrillère for their support in the experimental work.
Fig. 7. Estimated wear rates of the tribological 
couple wood pin/disc
20
15
10
5
0
disk
wood pin
w
ea
r r
at
e 
(×
10
–6
) (
m
m
3 /N
 m
)
C1
C1+
F10
1
C2+
F10
1
C1+
F10
2
C2+
F10
2C2
samples
REFERENCES
1. M. A. DJOUADI, C. NOUVEAU, P. BEER, M. LAMBERTIN: CrxNy Hard Coatings Depos-
ited with PVD Method on Tools For Wood Machining. Surf Coat Tech, 133, 134, 478 (2000).
2. C. NOUVEAU, E. JORAND, C. DECÈS-PETIT, C. LABIDI, M. A. DJOUADI: Influence of
Carbide Substrates on Tribological Properties of Chromium and Chromium Nitride Coatings:
Application to Wood Machining. Wear, 258, 157 (2005).
3. B. WARCHOLINSKI, A. GILEWICZ, Z. KUKLINSKI, P. MYSLINSKI: Hard CrCN/CrN
Multilayer Coatings for Tribological Applications. Surf Coat Tech, 204, 2289 (2010).
4. B. WARCHOLINSKI, A. GILEWICZ: Multilayer coatings on tools for Woodworking. Wear,
271, 2812 (2011).
5. E. TANRITANI , S. HIZIROGLU, N. AS: Effect of steaming time on surface roughness of
beech veneer. Build Environ, 41, 1494 (2006).
6. T. OHTANI, K. KAMASAKI, C. TANAKA: On Abrasive Wear Property During Three-body
Abrasion of Wood. Wear, 255, 60 (2003).
7. ASTM G99 – 95c, Standard Test Method for Wear Testing with a Pin-on-Disk Apparatus.
8. F. H. STOTT: The Role of Oxidation in the Wear of Alloys. Tribol Int, 31 (1–3), 61 (1998).
9. A. DEACONESCU, T. DEACONESCU: Aspects Regarding the Roughness of Surfaces Ob-
tained by Lapping. J Balk Tribol Assoc, 12 (1), 16 (2006).
10. F. ZIVIC, M. BABIC, N. GRUJOVIC, S. MITROVIC, D. ADAMOVIC, G. FAVARO: A Com-
parison of Reciprocating Sliding at Low Loads and Scratch Testing for Evaluation of TiN
(PVD) Coating. J Balk Tribol Assoc, 18 (1), 80, (2012).


Wear performance of duplex treated low alloyed steel against wood (beech) as static partner

https://sam.ensam.eu/bitstream/handle/10985/9990/LABOMAP_JBTA_2014_NOUVEAU.pdf?sequence=3&isAllowed=y

Wear performance of duplex treated low alloyed steel against wood (beech) as static partner

Abstract

Similar works

Full text

Available Versions

SAM; the Arts et Métiers ParisTech open access repository